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The ice mission near the start is easier than it looks Collect as many crates as possible without using any utilities then use the jet pack to get up to the next section near the guard Collect all the crates there and stand on the polar bears head Point the flame thrower at a spot just to the left of the guard and fire You should get through the barrier protecting him and the flames should send him into the water

Walk forward until you get both the uzis then jet pack over onto the polar bear Grab the battle axe and shoot the next closest crate with the uzi standing back to avoid damage to blow a hole giving you access the area where the Guard worm is Use your other jetpack to go behind him then blast him into the water with your other uzi